1968 Firebird Rear Suspension Question

[Zyman]

My 1968 Firebird has SpeedTech control arms, SpeedTech Front sway bar, Viking Coil overshocks & springs front; DSE 3" drop leaf springs & shackle kit w/Delrin bushing, Viking smoothbody rear shocks. The chassis has Pro Touring F-Body – Solid Body Bushings and GEN II Sub-Frame Connectors.

When proceeding from a stop and turning under acceleration, the 4L60E tranny shifts to 2nd in mid turn and the rear end wants to unsettle.



Would adding a rear sway bar address this? If so, any reason to consider any particular brand over another, I would lean to a SpeedTech rear since I have theirs up front and DSE does not make a leaf spring rear sway bar.